Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 7 of 7 for “"four-dimensional computed tomography"”.
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Approaches for respiratory motion compensation in positron emission tomography imaging
… quantitation results in positron emission tomography (PET) imaging. Traditional gated acquisition approach corrects motion artifacts by generating a snapshot sequence. Each snapshot, however, is of poor image quality due to insufficient photon counts. This dissertation addresses the problem …
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Moving Phantom Study of Stereotactic Body Radiation Therapy for Lung Cancer
… large range irregular breathing motions (=20mm). Four-dimensional computed tomography (4DCT) and cone beam computed tomography (CBCT) are important methodologies for SBRT, but previously have only been used to evaluate regular patterns. For targets moving regularly or irregularly within a small …
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A Patient-Specific Multiscale Model of Mechanical Ventilation of COVID-19-afflicted Lungs
… and mechanically ventilated patients using four-dimensional computed tomography (4DCT) imaging data from COVID-19 patients. Models presented in this thesis were designed to provide insight into airflow redistribution and volume and pressure differentials on a regional basis. One model was …
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Evaluation of Artifacts In Experimental Cine 4D Ct Acquisition Methods
<p>Four-dimensional computed tomography (4D CT) has increased the accuracy of radiation treatment planning for patients in whom the extent of target motion is large. 4D CT has become a standard of care for radiation treatment simulation, allowing decreased motion artifacts and increased …
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Thoracic Target Volume Delineation Using Various Maximum-Intensity Projection Computed to mography Image Sets For Stereotactic Body Radiation Therapy
… uncertainty of target position. The adoption of four-dimensional computed tomography (4D-CT) has allowed us to determine how a tumor moves with respiration for each individual patient. Using information acquired during a 4D-CT scan, we can define the target, visualize motion, and calculate dose …
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Thoracic Radiotherapy Treatment Planning With Cine Pet/Ct
… uncertainty in radiotherapy treatment planning. Four-dimensional computed tomography (4D-CT) is a useful tool to image tumor motion during normal respiration. Treatment margins can be reduced by targeting the motion path of the tumor. The expense and complexity of 4D-CT, however, may be …
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Motion Estimation and Motion-Compensated Reconstruction for Four-Dimensional Cone Beam Computed Tomography (4D-CBCT)
… cause for tumor localization uncertainty and four dimensional (4D) cone beam computed tomography (CBCT) has been developed to locate tumor in each respiration phase to better estimate the possible motion range of the tumor motion during the treatment. However, 4D-CBCT reconstructed by …